Shorts test.

Started by jvthorsley, February 09, 2023, 05:25:37 AM

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jvthorsley

Hi Curtis
As you may be aware from previous communications on this Forum & emails I frequently run the Shorts test using Workstation 4.3 on my ProTrack & Scanner setup.
The program readily shows when there is a short under whatever value it is set at.
But doesn't tell you if you have an open circuit.
Is this something you might include in a future update?
Would the same problem occur with the 3200S?

admin

Wouldn't a regular scan find an open circuit?
The most important troubleshooting tool is your eyes.

jvthorsley

Hi Curtis
Yes it does show on the high resistance test.
If the trace is south of the stored trace its open circuit, and if its north of the stored trace there is a short circuit.
This all refers to the test using a bank of sixty four  47 K Ohm resistors.
One end to COM and the other end to each channel.
I run the shorts test first that shows all links that should be there on a 64-way IDC connector.
Plus any that shouldn't be there.
Then run the high resistance test at settings of 1 KHz, 100 K Ohm, 20 V.
The high resistance test shows all sorts of nasty goings on under plug / socket housing as discussed on this Forum.
But as the low resistance test comes first it would be useful to see any open circuits that shouldn't be there.

admin

By saying "the low resistance test" are you referring to the Shorts Check that is run before a normal scan? When the Shorts Check is run is the 47Kohms fixture attached? If so then an open would not really be an open (horizontal signature). It seems like your high resistance test would detect opens as well.
The most important troubleshooting tool is your eyes.

jvthorsley

#4
Hi Curtis
Yes I am referring to the Shorts Test.
The shorts test is looking for anything up to 5 Ohms.
Possible to call an open as anything more than 10 K Ohm?
But adjustable as the Shorts Test setting.
Probably not enough demand for this!
As said the 47 K Ohm Resistors give a 45 Deg. trace so anything previously not recorded north of the trace is a short, and anything south of the trace is an open circuit.
The attached photos show the more severe kind of damage that can occur at 12 V.D.C. with lots of available current!!